[
https://issues.apache.org/jira/browse/CASSANDRA-14248?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17090947#comment-17090947
]
Jonathan Ellis commented on CASSANDRA-14248:
--------------------------------------------
Hi Jordan,
It looks to me like SSTableTidier does in fact include SASI components and the
only thing stopping it is that SSTableIndex usually deletes them first. I
created a patch to remove that redundancy
([https://github.com/jbellis/cassandra/tree/14248)] and now SSTT is doing its
job. Am I missing something?
> SSTableIndex should not use Ref#globalCount() to determine when to delete
> index file
> ------------------------------------------------------------------------------------
>
> Key: CASSANDRA-14248
> URL: https://issues.apache.org/jira/browse/CASSANDRA-14248
> Project: Cassandra
> Issue Type: Bug
> Components: Feature/SASI
> Reporter: Jordan West
> Assignee: Jordan West
> Priority: Normal
> Fix For: 3.11.x
>
>
> {{SSTableIndex}} instances maintain a {{Ref}} to the underlying
> {{SSTableReader}} instance. When determining whether or not to delete the
> file after the last {{SSTableIndex}} reference is released, the
> implementation uses {{sstableRef.globalCount()}}:
> [https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/index/sasi/SSTableIndex.java#L135.]
> This is incorrect because {{sstableRef.globalCount()}} returns the number of
> references to the specific instance of {{SSTableReader}}. However, in cases
> like index summary redistribution, there can be more than one instance of
> {{SSTableReader}}. Further, since the reader is shared across multiple
> indexes, not all indexes see the count go to 0. This can lead to cases where
> the {{SSTableIndex}} file is incorrectly deleted or not deleted when it
> should be.
>
> A more correct implementation would be to either:
> * Tie into the existing {{SSTableTidier}}. SASI indexes already are SSTable
> components but are not cleaned up by the {{SSTableTidier}} because they are
> not found with the currently cleanup implementation
> * Revamp {{SSTableIndex}} reference counting to use {{Ref}} and implement a
> new tidier.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]